1. Field of Invention
This invention relates to perimeter security barriers, and in particular but not exclusively, to barriers that provide an effective perimeter protection against wilful intrusion around airports and the like.
2. Discussion of Related Art
Conventional perimeter security barriers are designed to withstand vehicle impacts but differ from road crash barriers in that they resist vehicle impacts in a direction substantially perpendicular to the perimeter barrier. Conventional road crash barriers, by contrast, are designed to deflect vehicles impacting the fence an angle of 15 to 25 degrees relative to the fence (i.e. low angles) at speeds up to 110 km/h (68 mph).
The problem with conventional perimeter security barriers is that they are unable to prevent transgression of heavy impacting vehicles. They are of solid construction, usually of concrete blocks, making them unsightly and difficult to install. It is therefore an aim of the present invention to provide a perimeter security barrier that can arrest heavy vehicle impacts (e.g. goods vehicles).